Occasional engine malf(n) light & jerky transmission

[Cook1234]

any experts out there who can help me address this issue.

 

i drive a 8year old lexus, mileage 113k. regularly serviced at 10k intervals.

 

occasionally i get this engine malfunction yellow light on and jerky gear shifts, especially at low speeds. this seems to disappear after driving for a while. This issue has been happening for the past 6month-1year already. car is otherwise ok.

 

 

1) if i take it to the service workshop and this problem doesn't happen then, can those guys diagnose the problem?

 

2) if it is a serious fault, by now car would have broken down already rite?

 

can any experts advise me??

 

many thanks

 

[R_aquarii]

got a similar problem as what you mention.

ECL code is p1780 which is N/P safety switch. which turn out to be my transmission problem

better go to a reliable workshop and check the ECL code

[Yeobh]

Suspect auto trans multi-clutch plates surfaces maybe be dirty/slip due to presence of moisture or sludge. The other possibilty is loose ground wire connection from trans to chasis.

[Cook1234]

Suspect auto trans multi-clutch plates surfaces maybe be dirty/slip due to presence of moisture or sludge. The other possibilty is loose ground wire connection from trans to chasis.

 

 

can any normal workshop diagnose which is which and rectify it? or must go back to borneo?

[Yeobh]

AD usually have the original dealer scanner which have very much more software power to excess the on-board computers than those aftermarket type, widely use by the independent shops. Many aftermarket scanners may not have the software to download info fro transmission module and other such as SRS module ( air bag).

[Vincentthung]

any experts out there who can help me address this issue.

 

i drive a 8year old lexus, mileage 113k. regularly serviced at 10k intervals.

 

occasionally i get this engine malfunction yellow light on and jerky gear shifts, especially at low speeds. this seems to disappear after driving for a while. This issue has been happening for the past 6month-1year already. car is otherwise ok.

 

 

1) if i take it to the service workshop and this problem doesn't happen then, can those guys diagnose the problem?

 

2) if it is a serious fault, by now car would have broken down already rite?

 

can any experts advise me??

 

many thanks[/quote

 

Bro my Honda jazz also hv this same problem mileage abt 115000km

I also run know what is wrong.heard khang motor in sin Ming special in gearbox problem.intend to ask them check it out

Edited November 2, 2011 by Vincentthung

[Watwheels]

How do you know it's a gearbox problem? Between which gears do the jerking occurs?

 

If you have been following some kind of servicing schedule which includes intervals of changing of gearbox oil the gearbox should be working fine.

 

If you feel jerks at low speed it can mean other things like the fuel injectors are clogged with carbon particles at the injector tip. Usually high mileage or cars that's 4~5 years with owners who drive light-footed have this problem. When the injectors are clogged the engine is experiencing some kind of starvation, not enough fuel injected into the combustion chamber and the jerking starts. After driving a while cos of constant acceleration it might have remove some of the clogging, that might explain the jerking stopped.

 

I cannot be sure if the injectors are clogged. One way to eliminate it is to use injector cleaners. Mix with your petrol and let it do its work. Or you can take your car to an empty expressway and redline your engine.

 

Jerking can also be pre-ignition. The carbon particle build-up in the combustion chamber. The carbon particles pre-igniting the air-fuel mixture before your spark plug does causing the engine to lose power suddenly. Symptoms are "pinking" sounds when you off the ignition after driving. Sounds as if something is holding a small hammer hitting your engine from the inside. If this is the case, try using a higher RON rating of petrol like RON98 for the next few tanks.

 

BTW from my past experiences if the gearbox fail or is going to fail, you will hear very distinctive gear grinding sound. And you will know at which gear you will hear it. If do not hear this kind of sounds, your gearbox is fine.

 

 

[Detach8]

have you ever had your transmission fluid replaced? 113k is quite a bit of mileage, you should have replaced it at least once. sounds like a tranny issue but i don't drive a lexus. when your tranny warms up it will build oil pressure and parts in the tranny move quicker and hold better.

 

a good mechanic with a lexus computer should be able to read the fault codes stored in your car.

Edited November 2, 2011 by Detach8